Compartmentation: Cells and Tissues

Question 1

What are the three major anatomical compartments?

Answer 1

Cranial cavity, thoracic cavity and abdominopelvic cavity.

Question 2

What is the role of biological membranes?

Answer 2

Separate one compartment from another.

Question 3

What do biological membranes consist of?

Answer 3

Double layer (bilayer) of phospholipids with protein molecules inserted in them. Small amount of carbohydrates.

Question 4

What are the 4 functions of the cell membrane?

Answer 4

1. Physical isolation
2. Regulation of exchange with the environment
3. Communication between the cell and its environment
4. Structural support

Question 5

What is the relationship between metabolic activity of a membrane and its protein content?

Answer 5

The more metabolically active the membrane is the more protein it contains.

Question 6

What are the three types of lipids found in the membrane?

Answer 6

1. Phospholipids (major lipid)
2. Sphingolipids (lipid rafts)
3. Cholesterol (increases viscosity, alters permeability).

Question 7

What are amphipathic phospholipids?

Answer 7

They have a hydrophilic head and hydrophobic tail.

Question 8

What are micelles and what are they important for?

Answer 8

They are droplets of phospholipids in a half sphere shape. Important for lipid digestion.

Question 9

How are liposomes different from micelles?

Answer 9

They have an aqueous center.

Question 10

What makes up the structure of cell membrane lipids?

Answer 10

Phosphate group head, glycerol back bone, and two fatty acid chains for the tail.

Question 11

What makes up the fluid mosaic model of the cell membrane?

Answer 11

Proteins dispersed throughout the membrane and the extracellular surface contains glycoproteins and glycolipids.

Question 12

How are proteins bound to the membrane?

Answer 12

Can be loosely or tightly.

Question 13

How many different types of proteins can be inserted into the membrane?

Answer 13

10-50 different types.

Question 14

What are the two types of integral proteins?

Answer 14

Transmembrane and lipid anchored proteins.

Question 15

What are peripheral proteins?

Answer 15

They attach to integral proteins.

Question 16

What are the roles of peripheral proteins?

Answer 16

1. Participate in intracellular signaling

2. Form submembranous cytoskeleton

Question 17

What are the roles of integral proteins?

Answer 17

1. Membrane receptors
2. Cell adhesion molecules
3. Trasmembrane movement
4. Enzymes
5. Mediators of intracellular signaling

Question 18

How are lipid anchored proteins linked to phospholipids?

Answer 18

Sugar phosphate chain links them to the fatty acids of the phospholipid.

Question 19

What are lipid anchored proteins commonly associated with?

Answer 19

Sphingolipids instead of phospholipids.

Question 20

What do lipid rats contain?

Answer 20

An abundance of proteins important in cell signal transduction.

Question 21

What are the two types of cell membrane carbohydrates and where are they found on the membrane?

Answer 21

Glycoproteins and glycolipids. They are always extracellular.

Question 22

What are glycoproteins?

Answer 22

A protein with a carbohydrate attached.

Question 23

What are glycolipids?

Answer 23

A lipid with a carbohydrate attached.

Question 24

What are the functions of glycoproteins?

Answer 24

Structural, transport and immunologic molecules, hormones, enzymes, and cell-cell recognition.

Question 25

What is the function of glycolipids?

Answer 25

They serve as recognition sites for cell to cell interactions.

Question 26

What is cholesterols function in the membrane and where is it positioned?

Answer 26

Positioned between phospholipid tails to add flexibility and help to make the membrane impermeable to small water-soluble molecules.